Sewage samples are collected weekly from water reclamation facilities that serve Athens Clarke County (WRF A and WRF B). Samples are tested to detect and measure SARS-CoV-2, the virus that causes COVID-19.
We measure the virus by detecting two genes specific to SARS-CoV-2, the N1 and N2 nucleocapsid genes, using RT-qPCR. The N1 and N2 gene targets are measured and reported as a concentration, in number of gene copies per liter of wastewater. Note that the viral copies per liter are shown in a log scale, such that log 5, for example, equals 10^5 copies or 100,000 copies per liter. The theoretical limit of detection (LOD) is noted.
We predict that changes in the concentration of SARS-CoV-2 in wastewater will reflect the community trends of circulating COVID-19 infections. The daily number of newly reported COVID-19 cases in Athens-Clarke County (grey) appear alongside the 10-day moving average of new cases (yellow). Changes in SARS-CoV-2 in wastewater may precede changes in reported cases because of lags in clinical testing.
Wastewater surveillance is an emerging tool for monitoring disease outbreaks. Coupled with clinical surveillance, wastewater surveillance can be used to estimate the level of viruses circulating in local population.
To better understand the outbreak of the novel Coronavirus disease-19 (COVID-19) on a local level, we are monitoring wastewater samples from water reclamation facilities in Athens, GA. Wastewater samples are collected weekly and tested to detect the disease-causing virus, SARS-CoV-2.
Each sample is a composite of the wastewater received by the water reclamation facility in a single day. By examining these samples, we are capturing a snapshot into the health of the entire community that contributes to the sewershed. This wastewater-based research provides a new approach to epidemiology; sewage surveillance may be used to predict the total burden of disease at a community-scale, without extensive clinical sampling.
We are sharing here some of the preliminary results of our wastewater monitoring program. Our objective is to critically examine the use of SARS-CoV-2 wastewater-based epidemiology for the detection and surveillance of SARS-CoV-2 in our local community.
We are developing and evaluating our methods in real-time. We will share with you our weekly results and newest developments. This data is intended to complement clinical-based COVID-19 surveillance data, that will together, inform public health decisions.
To learn more about national surviellence efforts, using wastewater-based epidemiology, please visit the CDC’s National Wastewater Surveillance System (NWSS).
Since May 2020, sewage samples have been collected weekly from the water reclamation facilities (WRFs) that serve Athens-Clarke County. Samples are collected from a 24-hour composite of the influent wastewater received by each WRF.
Samples are processed by the Lipp Laboratory at the University of Georgia to detect and measure the abundance of SARS-CoV-2 virus in wastewater.
Viral RNA, the genetic material of the SARS-CoV-2 virus, is extracted from each sample using the QIAamp Viral RNA Mini Kit.
The viral RNA is then measured using Real-Time RT-PCR Assays, following the CDC’s test protocol for the N1 and N2 SARS-CoV-2 nucleocapsid genes.
The N1 and N2 gene targets are measured and reported as a concentration, by the number of gene copies measured per liter of wastewater.
A more detailed explanation of the research methods can be found here.
Main Figure (again)
Total Viral Load
Number of Assays positive/week
This weekly monitoring is conducted in partnership between Athens-Clarke County Utilities, the Lipp Laboratory, and the College of Public Health at the University of Georgia.
Dr. Erin Lipp
Megan Lott, PhD Student
William Norfolk, PhD Student
Megan Robertson, PhD Student